Background and Aims: A national survey of photodynamic therapy (PDT) was carried out in order to understand the present situation in Japan and the efficacy of PDT for gastric cancer.
Material and Methods: A questionnaire concerning with PDT was sent to all hospitals performing or previously performed PDT. The answers were collected and analyzed. An additional investigation about efficacy of PDT for gastric cancer was conducted for the main 3 hospitals.
Results: In 18 of 19 responded hospitals, PDT was performed for 386 cases of superficial early gastric cancer and for 27 cases of advanced gastric cancer. In the 3 main hospitals, a complete response was achieved in 42 of 57 patients (73.7%) of superficial early gastric cancer not indicated for surgery or other endoscopic treatments such as endoscopic submucosal dissection. No serious complication occurred.
Conclusions: PDT has been shown to be a safe and effective treatment for early gastric cancer, not only for the intramucosal type, but also for the submucosal invasion. PDT will be one of the important endoscopic treatments for gastric cancer especially in a super ageing society like Japan.

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Background and aims: Recently novel picosecond duration lasers (ps-lasers) have been developed for the treatment of multicolored and recalcitrant tattoos, and safety and efficacy have been reported. We therefore hypothesized that the ps-laser could be an alternative treatment for dermal pigmented lesions and performed a retrospective review to evaluate the efficacy and safety of the ps-laser could be an alternative treatment for dermal pigmented lesions and performed a retrospective review to evaluate the efficacy and safety of the ps-laser.
Subjects and methods: A retrospective photographic review of 10 patients with dermal pigmented lesions was performed (ages from 4 months to 52 yr), 6 nevus of Ota, 3 ectopic Mongolian spots and 1 Mongolian spots. The patients were treated in the Ohshiro Clinic with picosecond 755 nm alexandrite laser (ps-Alex laser) and picosecond 1064 nm Nd:YAG laser (ps-Nd:YAG laser) from April 2014 to December 2015 (ps-Alex laser, 7 patients; ps-Nd:YAG laser, 3 patients, 1 to 3 treatment sessions). Improvement was evaluated as percentage of pigmentation clearance comparing the baseline findings with those at 3 months after the final treatment using a five category grading scale: Poor, 0-24%; Fair, 25-49%; Good, 50-74%; Excellent, 75-94%; and Complete, 95-100% improvement. Adverse events were also assessed.
Results: All ten patients obtained clinical improvement ranging from fair to excellent. Treatment with the ps-Alex laser caused transient hyperpigmentation followed by improvement to complete resolution at 3 months follow-up. The ps-Nd:YAG laser caused severe transient erythema and swelling but no post-inflammatory hyperpigmentation.
Conclusions: Our results suggest that the 755 nm and 1064 nm ps-lasers are efficacious for the treatment of dermal pigment lesions, with minimum adverse events.

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Objectives: The introduction of diode lasers in dentistry had several advantages, principally consisting on the reduced size, reduced cost and possibility to beam delivering by optical fibbers. Up today only the wavelengths around 810 and 980 nm were the most utilized in oral surgery but recently more different lasers had been proposed.The aim of this study was to compare the efficacy of four diode laser wavelengths (810, 980, 1470 and 1950 nm) for the ablation of soft tissues.
Material and Methods: Specimens were surgically collected from the dorsal surface of four bovine tongues and irradiated by four different diode wavelengths. Thermal increase was measured by two thermocouples, the first at a depth of 0.5 mm, and the second at a depth of 2 mm.
Initial and final surface temperatures were recorded by IR thermometer.
Epithelial changes, connective tissue modifications, presence of vascular modification and incision morphology were histologically evaluated by two blind pathologists.
Results:The time necessary to perform the excision varied between 271 seconds (808 nm, 2W) and 112 seconds (1950 nm, 4W). Temperature increase superficial level varied from 16.3° (980 nm, 4W) and 9.2° (1950 nm, 2 W). The most significant deep temperature increase was recorded by 980 nm, 4 W (17.3°) and the lowest by 1950 nm, 2 W (9.7°). The width of epithelial tissue injuries varied between 74 μm from 1950 nm diode laser at 2 W to 540 μm for 1470 nm diode laser at 4 W.
Conclusions: The quality of incision was better and the width of overall tissue injuries was minor in the specimens obtained with higher wavelength (1950 nm) at lower power (2W).

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Aim: The aim of this in vitro study is to evaluate the shear bond strength of reattached fractured incisor fragments using Er,Cr:YSGG laser and conventional acid etching without additional tooth preparation.
Material and methods: Forty extracted human teeth were divided in two groups of 20 each (Groups A and B). In Group A, fractured surface was treated by an Er, Cr: YSGG laser system (Waterlase MD, Biolase Technology Inc., San Clemente, CA, USA) operating at a wavelength of 2,780 nm and frequency of 20 Hz. In Group B, fractured surface was etched using 37% phosphoric acid (Scotchbond, 3M). In both the groups, further subdivision with 10 sample each was made based on horizontal and oblique fracture. After laser or acid etching, all the samples were reattached using flowable composite resin and light cured. The samples were tested for shear bond strength.
Results: Mean shear bond strength for Group A (94.70±39.158) was lower as compared to Group B (121.25±49.937), although the difference was not statistically significant(p value=0.121). Similarly no statistical significant difference was observed amongst the subgroups. (p>0.05)
Conclusions: Er,Cr:YSGG laser etching in reattachment of fractured incisor fragment is a good alternative to conventional acid etching. Er,Cr:YSGG showed comparable efficiency in rebonding of fractured teeth fragment as acid etching.

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Background and aims: This study aimed to evaluate the efficacy of ibuprofen, bite wafer and low power red and infrared lasers in orthodontic pain management.
Subjects and methods: One hundred subjects were randomly assigned to 5 groups of 20 each. The patients in each group received one of the following treatments after the placement of fixed orthodontic appliances: 1. placebo medication, 2. ibuprofen, 3. bite wafer, 4. irradiation from a low level red laser (LLRL; 660 nm, 200 mW, 1 J/point, 6 points), 5. irradiation from a low level infrared laser (LLIL; 810 nm, 200 mW, 1 J/point, 6 points). A Visual Analogue Scale (VAS) was used to record pain intensity while chewing, biting, fitting front teeth, and fitting back teeth at 2 hours, 6 hours, bedtime, 24 hours, 2 days, 3 days and 7 days following arch wire placement.
Results: Significant between-group differences were found in pain at chewing, biting, fitting front teeth and fitting back teeth at all time points (p<0.001). Generally, VAS scores in the LLIL, ibuprofen and bite wafer groups were close to each other and significantly lower than those in the LLRL and control groups (p<0.05), which showed comparable pain level at most intervals. The infrared laser group (LLIL) showed significantly lower pain than all other groups at some points over the experiment (p<0.05).
Conclusions: A single irradiation from a low level infrared laser proved to be the best strategy for orthodontic pain control. Alternatively, chewing on a bite wafer could be recommended. These methods should be considered as suitable alternatives for ibuprofen in orthodontic patients.

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Aims: This is an extended case series of patients treated with an Erbium, Chromium: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) laser as an adjunct to scaling for the management of intrabony defects.
Materials and methods: 46 patients with 79 angular intrabony defects associated with pocket depths of >5mm, and a mean age of 53 ± 9 years presenting with chronic periodontitis were included in the analysis. All patients underwent a localized minimally invasive closed flap surgery utilizing Er,Cr:YSGG laser therapy. Final radiographs and pocket depths were compared to pretreatment measurements with a time period of 8 ± 3 months.
Results: Treatment resulted in significant overall pocket depth reduction. The mean pre-op probing depth was 8.1 ± 1.9mm, reducing to 2.4 ± 0.9mm post-treatment. Bony infill of the defects was visible radiographically and there was an increase in overall radiographic coronal osseous height compared to a pre-treatment baseline. Radiographs of 15 of the defects were available for further measurements after >12 months, and showed in these sites there was a significant reduction in intrabony defect depth, but no change in suprabony bone height. 9 of the 15 sites showed 50% or more, bony infill of the intrabony defect.
Conclusions: The results demonstrate that the utilization of an Er,Cr:YSGG laser in a closed flap approach with chronic periodontitis may be of significant clinical benefit. Further studies using this laser surgical protocol are required to test these observations in well-designed randomized controlled trials.

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